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We established Q spectroscopy, a novel method for the study of alpha decay, by combining 4π detection scheme with a low-temperature microcalorimeter. A 4π metal absorber guarantees absolute measurement of radioactivity without energy loss in the source and absorber. As a clear demonstration of Q spectroscopy, the 241Am alpha source enclosed by a thin gold foil was measured below 100 mK. Its resulting energy spectrum has two dominant peaks with 10 keV FWHM. The more dominant one corresponds to the complete absorption of the Q value, the total decay energy, and the less dominant one to γ-ray escapes. Consequential one-to-one correspondence with high-energy resolution appears between mixed radioisotopes and peaks in Q spectroscopy, which will simplify procedures of nuclear material analysis.

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Collectively, these results indicate that 1) tfASCs have similar characteristics as DP cells, 2) tfASCs have enhanced hair-regenerative potential compared with ASCs, and 3) tfASCs even at late passage can make new hair follicles in a hair reconstitution assay. Because DP cells are difficult to isolate/expand and ASCs have low hair inductivity, tfASCs and tfASC-CM are clinically good candidates for hair regeneration.

We report the recent progress on high resolution alpha spectrometers that use metallic magnetic calorimeters. The detector is composed of a meander-type magnetic calorimeter and a gold-foil absorber. The thermal connection between the magnetic sensor and the absorber consists of annealed gold wires. The signal rise time is found to be as expected, with the electronic thermal conductance of gold wires. The energy resolution of a 3.2 keV FWHM is obtained for 5.5 MeV alpha particles with possibilities for further improvements.